4 New NGK Iridium IX Spark Plugs CR9EIX # 3521 by NGK

Product Information

Torque the spark plug up to your manufacturer’s recommended settings. If you don’t have a torque wrench, then get the plug hand tight and then add a ½ turn for a plug with a gasket, and more like a ¼ turn for a tapered spark plug. Over-tightening can snap the spark plug – a nightmare. This nifty little tool only costs a few quid and will help you set the correct gap for your spark plug. However, modern plugs are almost all motorcycle-specific fit and so they come ‘pre-gapped’ and you won’t need to touch them. If you’re running a classic bike, you’ll probably need to set your gap and if your bike’s not running right, a gap tool can help you rule out a potential incorrect gap issue.

Harley Davidson Spark Plug Cross Reference - Biker Rated Harley Davidson Spark Plug Cross Reference - Biker Rated

Iridium alloy has extremely high melting point, perfect for today’s high-tech, high-performance engines A spark plug electrode is litterally at the absolute hottest part of the engine. It is where combustion starts, when compression is the highest it's going to be, and where a lightening bolt (that is a plasma discharge) is purposfully formed. Iridium alloy has extremely high melting point, perfect for todays high-tech, high-performance engines The installation guide error on the fakes may cause even more damage if anyone also ends up using thread compound or copper slip. Using such products renders torque readings inaccurate by at least 20% so they should never be used. Modern plugs feature a special zinc coating so they simply don’t need it. NGK released a tech bulletin about this, which you can read in our other article in the link below: Just put iridium plugs in my K5 and it seems to have cleaned up a very slight light burble of a misfire that I had.you will notice in the first picture by -AK- you can see the spark plug throat, that is the electrode and ceramic insulator and then space between the threaded material and the electrode/ceramic insulator. How far up inside the spark plug does that space go? The image of the spark plugs above shows four common conditions that you’ll find your spark plugs in. From left to right the plugs are Normal, Rich, Lean and Very Lean. Full descriptions below. NGK is the brand leader in the UK spark plug market and are the world's biggest supplier to many major car manufacturers. Each and every one of their products are designed to meet the most rigorous standards and are the professionals' choice because of their quality and technical excellence. Their plugs can be found in use by teams in F1, WRC and MotoGP. Put simply, NGK genuine spark plugs are the workhorse at the heart of smooth-running engines around the world. A regular spark plug uses a copper central electrode whereas an iridium spark plug uses, you guessed it, iridium.

NGK Iridium IX Spark Plugs CR9EIX - Summit Racing

PLEASE NOTE – This article was written a few years ago so not all information provided may be accurate. For example, on some part numbers, NGK now uses Laser Etching instead of stamping, so the font information may not be accurate. Another Sparking Discovery Motorcycle spark plugs usually last around 16,000 miles, or at least this is when most manufacturer service schedules recommend you change them. That's typically once every other major service. However if you use Iridium spark plugs they will last a lot longer, usually well over 30,000 miles. As stated above, the illustrations on the rear show installation procedures for an M14 threaded spark plug. Unfortunately for Mr Counterfeit, CR9EIX spark plugs have an M10 sized thread! This fatal error has already fulfilled our suspicions that they’re indeed fake, and we haven’t even seen the plugs yet! M10 (10 mm) threaded plugs with a gasket show just 10-12nm of torque are needed for aluminium heads. Now compare this to an M14 plug, where we see over double the amount: 25-30nm. Torquing down an M10 plug to 30nm will most definitely cause either distortion to the plug and eventually snap into bits, or the cylinder head thread will strip; not good. Thread diameters of 10mm, 12mm, and 14mm are the most common. In fact, when it comes to motorcycles, it's rare to find any other sizes in use.

Not sure if this is because the old plugs were past their best or if the new ones are better. :dunno It gets better, the installation guides on the rear of the inner boxes are for an M14 (14mm) diameter threaded spark plug, not M10 (10mm) that CR9EIX features! A spark plug fouls with every single power stroke of the engine, as the fuel burns a deposit of soot forms on the electrode. Form enough deposit, the gap resistance changes and the plug either is resisted out or shorted out, neither of which will fire the cylinder.